ONLINE spending in the US during the first 48 days of the holiday season reached $20.65 billion, marking a 25 per cent increase versus a year earlier, according to com Score Networks, a research firm.%%Consumers spent more than $643 million during the weekend of December 16-17, up 34 per cent compared to last year. However, the highest single-day total for online spending was December 13th, when consumers shopped for goods worth $667 million, up 20 per cent from last year.